Narrative:

Initial contact with msp departure control was blocked by another aircraft after takeoff on runway 22 at msp. We seemed to be closing on previous departure, turbo-propeller aircraft in our medium large transport at this time. Departure controller's second transmission instructed a turn to what I understood to be X degrees. I initiated a rapid left turn to X degrees in order to gain sep from previous departure aircraft. About 45 seconds later we saw a northeast bound large transport at about 5000', at our 3 O'clock position, at about 2 mi. I leveled at 4200' as the controller also pointed out this traffic and told us to maintain our altitude. We passed behind and below the 5000' traffic, and no evasive action was required. It is entirely possible that I misunderstood the controller's heading instructions, although there did not seem to be any doubt in my mind at the time. Our call sign was X and the heading to our initial fix, odi, is X degrees. I am certain that I was distracted by the frequency congestion, and the proximity of the previous departure. I may have preprogrammed myself for the X degree heading, and in my haste to gain sep from the aircraft at my 12 O'clock, turned to X degrees.

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Original NASA ASRS Text

Title: MLG TURNED TO WRONG HEADING AND CAUSED A CONFLICT.

Narrative: INITIAL CONTACT WITH MSP DEP CTL WAS BLOCKED BY ANOTHER ACFT AFTER TKOF ON RWY 22 AT MSP. WE SEEMED TO BE CLOSING ON PREVIOUS DEP, TURBO-PROP ACFT IN OUR MLG AT THIS TIME. DEP CTLR'S SECOND XMISSION INSTRUCTED A TURN TO WHAT I UNDERSTOOD TO BE X DEGS. I INITIATED A RAPID LEFT TURN TO X DEGS IN ORDER TO GAIN SEP FROM PREVIOUS DEP ACFT. ABOUT 45 SECS LATER WE SAW A NE BOUND LGT AT ABOUT 5000', AT OUR 3 O'CLOCK POS, AT ABOUT 2 MI. I LEVELED AT 4200' AS THE CTLR ALSO POINTED OUT THIS TFC AND TOLD US TO MAINTAIN OUR ALT. WE PASSED BEHIND AND BELOW THE 5000' TFC, AND NO EVASIVE ACTION WAS REQUIRED. IT IS ENTIRELY POSSIBLE THAT I MISUNDERSTOOD THE CTLR'S HDG INSTRUCTIONS, ALTHOUGH THERE DID NOT SEEM TO BE ANY DOUBT IN MY MIND AT THE TIME. OUR CALL SIGN WAS X AND THE HDG TO OUR INITIAL FIX, ODI, IS X DEGS. I AM CERTAIN THAT I WAS DISTRACTED BY THE FREQ CONGESTION, AND THE PROX OF THE PREVIOUS DEP. I MAY HAVE PREPROGRAMMED MYSELF FOR THE X DEG HDG, AND IN MY HASTE TO GAIN SEP FROM THE ACFT AT MY 12 O'CLOCK, TURNED TO X DEGS.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.